noun
: a cluster of stars in which all the individual members may be discerned with an optical aid and which is much less compact and has fewer members than a globular cluster ; often : a galactic cluster
noun
: a cluster of stars in which all the individual members may be discerned with an optical aid and which is much less compact and has fewer members than a globular cluster ; often : a galactic cluster
Webster's New International English Dictionary. Новый международный словарь английского языка Webster. 2012